Slideshow: The Rise of Stiletto Networks - Top 5 Women's Power Circles

As Women’s History Month kicks off, we profile a women’s movement lurking beneath the scenes across several industries -- including the startup world.

We all know of Women 2.0, the S.H.E. Summit and other professional women’s conferences that attract ambitious females from across the country to network, learn about an industry and advance their careers at a single event. (And if you haven’t attended one, go register, stat.)

But a different trend is propelling women toward success: stiletto networks.

Executive and entrepreneurial women are meeting regularly in groups of no more than 10 to 12 for dinner at chic restaurants, poker nights in their redecorated high-rises, or their company’s boardrooms during business afterhours. They meet to talk economic trends, business deals, political lobbying, and the joys and woes of working motherhood. Personal matters are not off limits but professional topics take precedence.

“Women are opening their Rolodex and wallets on each other’s behalf,” Ryckman says. “They’re forming strategic alliances and partnerships with women who are their friends and business partners.”

Modern Businesswomen’s History 101: Cross-Industry Coalitions

Ryckman says that if we rewind 20 to 30 years ago, there was room for only one token woman executive in each company. “Women couldn’t share information with each other because they feared that one colleague could knock them off that perch,” she says. “So peer groups had to be cross-industry. Women were meeting not to get ahead, but to make friends with other professional women who weren’t direct competitors.”

Today, the groups remain intentionally small, but in aggregate they number in the tens if not hundreds of thousands of women in the U.S. From C-suite execs, to young entrepreneurs, to mothers launching businesses, women of all age groups are forming these intimate networks. Also, as individual members attend other larger meetings across the country, these circles are interlocking and becoming increasingly powerful, according to Ryckman.

Girls Raising recently hosted a pitch contest at the Rox Gallery in the Lower Eastside of NYC. Panel judge Deborah Jackson, CEO of Plum Alley and 85 Broads member, mentioned she adored Ryckman’s book, but added that it is almost out of date because so many circles have formed rapidly since the book’s May 2013 publish date.

It turns out Pauline Brown, Chairwoman of LVMH North America, and former private equity executive at the Carlyle Group, had recently launched a New York City dinner group. Inside the Beltway, Maryland-Based "Chicks in Charge" created the most successful fundraising pilot in the history of the Red Cross. Networks are sprouting deeper South, where women have launched "Sparkle" in South Carolina, and "Cake & Whiskey" in Kentucky.

We asked Ryckman to list the five hottest stiletto networks at the helm of this movement.

Click below to view the slideshow and meet the women of these power circles.

The Vault

Based in: Los AngelesCo-founders: Kim Moses, producer and director with six Emmys and two Golden Globes; and Willow Bay, Huffington Post editor.Stiletto Hotspot: “They prefer to meet at each other’s homes monthly, because it is a safer and more intimate space than an L.A. restaurant,” says Ryckman.

The Hollywood heavyweight and the journalist realized most businesswomen bring a heavy filter to large networking events. So the co-founders decided to invite the founder of Juicy Couture, the co-founder of the WNBA's L.A. Sparks and a top cardio surgeon to dinner and learn about their journeys to the top. They all responded yes.

Key results: Formed major business entertainment partnerships, and together organized international big screen openings for Hollywood films (the types that star Clint Eastwood)

It takes a lot to run intellectual property law at companies like Apple, Intuit, Google and eBay. The co-founders of ChIPs are armed with both undergrad degrees in engineering and Juris Doctors from top law schools. In 2005, these women realized they were practically the only women in their field, so they formed ChIPs to counsel each other through their careers.

Key results: Supported fellow members through job leaps, hosted each other’s baby showers and started a nationwide conference “The Road to Chief Counsel” to help young women navigate their legal careers. “A lot of these women actually ran litigation against each other’s tech companies,” says Ryckman, “but their relationship helped them come to a solution more quickly and less-costly.”

Lady Business

Based in: New York CityCo-founders: Alexa von Tobel, founder of LearnVest, and Alexa Hirschfeld, co-founder of Paperless PostStiletto Hotspot: Both accomplished Alexas invite New York City’s young female entrepreneurs to gather at Hirschfeld’s apartment in the Lower Eastside.

Lady Business gatherings are more akin to NYC nightlife. They sip cocktails and forge friendships that are both professional and personal. “This one is more of a party,” says Ryckman. “They talk business and boyfriends.”

Key result: At times, as good parties often do, the intimate cocktail hour turns into a party for over 100 of Silicon Alley’s elite. But the key members have connected each other to game-changing VC firms and angel investors.

Slideshow: The Rise of Stiletto Networks - Top 5 Women's Power Circles

Wafia (Women's Mafia) Poker Night

Barbara Corcoran and Cindy Gallop put on their poker faces for this stiletto network

Based in: New York CityFounder: Heidi Messer, founder of LinkShareStiletto Hotspot: Messer’s Tribeca high-rise is the HQ for Women’s Entrepreneur Poker Night, equipped with green felt tables and stacked chips.

After selling Linkshare in 2005 for $425 million, Messer (then in her thirties) was in no mood to retire so she began mentoring entrepreneurs. Today, she is re-inspired by the new wave of millennials who appear more proactive and tactical than ever. She started Wafia to help young “girlpreneurs” gain tips and funding.

Key results: Over a game of cards, young entrepreneurs brush up on business strategy, the art of bluffing and connect with local venture capitalists. Occasionally, women like Barbara Corcoran, Cindy Gallop and Kay Koplovitz make cameo appearances. She wants her women’s mafia to learn from prior generations of corporate vets and working women.

Slideshow: The Rise of Stiletto Networks - Top 5 Women's Power Circles

4C2B (Force to be (reckoned with))

The stiletto network movement is in full force in Alaska

Based in: Anchorage, AlaskaFounder: Liane Pelletier, President and CEO, Alaska Communications SystemsStiletto Hotspot: 4C2B member Betsy Lawler, president of First National Bank of Alaska, reserves the company’s boardroom for their network's meetings.

First National’s boardroom only seats twelve, including the attorney of Senator Lisa Murkowski, the chair of the U.S. Arctic Research Commission, and senior execs from BP and Alaska Airlines. As you could expect, oil and gas dominate the conversation.

Key result: The women combine forces to lobby for job creation and environmental safety issues when the Alaskan legislature meets. “These are all women thriving in a male-dominated environment, a male-dominated state, in male-dominated industries,” says Ryckman. “Yet they’re committed to improving the state economy and life there.”

As Pelletier told Ryckman, “It felt like we solved the world’s issues in an hour.”